The development of well drilling rig equipment and procedures for the past 30 or so years has shown slow progress, to the point that most rigs designs have remained relatively unchanged. This industry is well known for its "inertia" and reluctance to accept innovative change, even though various attempts have been made to achieve greater efficiency, self-containment and automation of well drilling equipment. For example, a multi-section, pinned, cantilever mast have been developed which allows a rig to be moved to a well site in a partially assembled state. Although erection time was reduced, and transportability enhanced, the remainder of the mechanical and fluid control components of the rig were such that the system has been very time consuming to assemble. It has been necessary to handle numerous pins, bolts, wirelines, hoses and electrical cables, as well as to manually handle the drill pipe during drilling operations.
Attempts to reduce erection time have primarily involved the use of telescoping masts, and masts with self-elevating drill floors. Efforts to simplify drilling operations have involved the development and use of top mounted drive systems and automatic pipe racking systems. In the area of transportation requirements, efforts have been made at reducing load sizes and quantities. Slab masts, as well as some substructures (typically trailers) have been developed to this end. In spite of all such efforts, applicant believes that nowhere in the current market place can a rig be found that combines any significant advancements in all of the aforementioned technological areas.
A general object of the present invention is to provide new and improved well drilling methods and apparatus which combine technological advances in the areas of erection techniques, drilling operations, and transportation.
Another object of the present invention is to provide new and improved methods and apparatus for transporting a unitized or modular drilling rig to the well site and erecting the same in reduced time.
Still another object of the present invention is to provide a drilling rig of the type described having a new and improved automatic pipe handling system that greatly increases productivity by significantly reducing the manpower needed for operating the same.
A further object of the present invention is to provide a new and improved drilling rig that is easy to move and set up, and which is fully automated and self-monitoring.
Another object of the present invention is to provide new and improved drilling rig apparatus and methods which reduce overall drilling and completion costs by limiting the time required to erect and assemble the rig at the well site, and by eliminating where possible the manual handling of consumables.